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arXiv · 2109.03376

Near-horizon microstructure and superradiant instability of black holes

Rong-Zhen Guo·Chen Yuan·Qing-Guo Huang
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Abstract

Ultralight bosons, as important candidates of dark matter, can condense around spinning black holes (BHs) to form long-lived ``boson clouds'' due to superradiance instability. The boson-BH system can be observed through gravitational wave detection and may become a new window to find traces of ultralight bosons. In this letter we explore the effects on the superradiant instability of BHs from the near-horizon microstructure. By introducing the reflection parameter near a BH horizon, we derived analytical results on the corrections to both energy levels of bosonic cloud and its characteristic frequencies of superradiance instability. Our results imply that the evolution of a boson-BH system and gravitational waves it emits would be influenced by the near-horizon physics of a BH.

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Rong-Zhen Guo, Chen Yuan, Qing-Guo Huang. 2021-09-08. Near-horizon microstructure and superradiant instability of black holes. https://doi.org/10.1103/physrevd.105.064029

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